1. Field of the Invention
The present invention relates to a cover disposed between an airbag, which is configured to be rolled from one end to the other end and be deployed upon receiving gas, and a body of a vehicle to which the airbag is attached. Moreover, the present invention relates to an airbag device including an airbag, which is configured to be rolled from one end to the other end and be deployed upon receiving gas, and a cover disposed between the airbag and a body of a vehicle to which the airbag is attached.
2. Related Technology
An airbag device is designed to protect occupants during collision by being attached to a vehicle. For occupant protection, since the airbag device needs to be deployed toward occupants from various directions, the airbag device is provided in various portions of the vehicle. Some airbag devices have an airbag provided in a folded state along an upper edge of an opening of a vehicle body (for example, a side window of a vehicle), and the airbag is deployed in a curtain shape during a side collision of the vehicle to protect the head portion and the like of an occupant.
In this type of airbag device, a folded airbag is stored in a flexible shape retaining cover formed in a cylindrical shape, for example, and the folded state is maintained. Further, the airbag is disposed such that the airbag and the shape retaining cover are covered by a protector extending in the longitudinal direction of the airbag so that the airbag does not interfere with a welded portion or the like of the vehicle body. By attaching the protector that surrounds the airbag and the shape retaining cover in this manner to the vehicle body using a bracket, for example, the airbag is attached to the vehicle body.
However, as in this type of airbag device, an airbag device having a curtain airbag that is deployed during a side collision, a deployment direction of the airbag needs to be reliably adjusted so that the deployed airbag is present between the head portion of the occupant and the window of the vehicle. Thus, it is also necessary to adjust a stored posture when storing the airbag in the shape retaining cover and when further storing the airbag stored in the shape retaining cover in the protector. To obviate this complication, an airbag device disclosed in Japanese Patent Application Laid-open No. 2009-23439 is proposed.
In the airbag device disclosed in Japanese Patent Application Laid-open No. 2009-23439, an engagement piece is formed in a protector, and an engaging portion engaging with the engagement piece is formed in a shape retaining cover. The engaging portion includes an inlet-side engagement hole, in which the engagement piece is inserted for engagement, and an outlet-side engagement hole through which an engagement hook at the tip end of the engagement piece, inserted in the inlet-side engagement hole for engagement, protrudes for engagement (see FIG. 2 of Japanese Patent Application Laid-open No. 2009-23439). With such a configuration, the airbag and the shape retaining cover are assembled into the protector to form such a unit that the airbag and the shape retaining cover are always arranged at a fixed position within the protector.
As described above, in an airbag device having a curtain airbag that is deployed during a side collision, it is necessary to reliably adjust the deployment direction of the airbag so that the deployed airbag is present between the head portion of an occupant and the window of the vehicle. When this is considered carefully, a situation that cannot be dealt with by the conventional technique may occur.
For example, when a vehicle is involved in a side collision with an obstacle such as a telegraph pole, the destroyed window glass may enter into the interior side of the vehicle. In this situation, according to the conventional technique, the entire airbag extending in the front-rear direction of the vehicle is guided so as to merely be deployed in a single direction along the window. Thus, the entire airbag is deployed very close to the window, the airbag may be damaged by the broken window glass, and the airbag may not be properly deployed.
In this situation, according to the conventional technique, the entire unitized airbag may be configured to be guided toward the inner side for each protector. However, if the entire airbag is guided toward the inner side, although it may be possible to obviate damage to the airbag caused by the broken window glass, the entire airbag is deployed also toward the inner side, and excessively large force may be applied to occupants. In particular, when the position of the head portion of an occupant is temporarily moved toward the window due to the impact during a side collision, the impact on the head portion may increase. To obviate such a situation, although it is necessary to accurately adjust the deployment direction of the airbag during a side collision according to the deployment position, the conventional technique cannot deal with this.
In order to accurately adjust the deployment direction of the airbag during a side collision according to the deployment position, the airbag may be twisted and attached to the body of the vehicle, for example, without using the unitized airbag as in the conventional technique. However, when the airbag is twisted and attached to the body of the vehicle, the twisting method may differ from operator to operator, and eliminating an individual difference between operators may lead to an increase in workload.